Only a sample and my English is not good. Anyway, it works!!!
Re : Request of reducing mortgage interest rate
Dear Sir / Madam,
Please be informed that I have applied for the mortgage on XXXXX with loans account number XXXXXXX and your reference number XXXXXXX. In recent years, the interest rate for the whole market drops from time to time. So I hope you can also reduce my mortgage interest rate to P-2.8 which is the reasonable level in the market nowadays.
So please consider my situation and should you have any query, please feel free to contact me through mobile phone number XXXX XXXX.
我怕銀行不會減得咁密 ... Don't worry about that. It all depends on market condition whether you could get any interest cut or not. There is no downside risk but only possibility to save a lot of interest.